/*
 * Copyright (C) 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.sctek.smartglasses.zxing;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.DecodeHintType;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.Result;
import com.google.zxing.ResultPoint;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
import cn.ingenic.glasssync.R;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Intent;
import android.content.pm.ActivityInfo;
import android.content.res.AssetFileDescriptor;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.os.Vibrator;
import android.util.Log;
import android.view.KeyEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.Window;
import android.view.WindowManager;
import android.widget.ImageView;

import java.io.IOException;
import java.util.Collection;
import java.util.EnumMap;
import java.util.Map;

/**
 * This activity opens the camera and does the actual scanning on a background thread. It draws a
 * viewfinder to help the user place the barcode correctly, shows feedback as the image processing
 * is happening, and then overlays the results when a scan is successful.
 *
 * @author dswitkin@google.com (Daniel Switkin)
 * @author Sean Owen
 */
public final class CaptureActivity extends Activity implements SurfaceHolder.Callback {

  private static final String TAG = CaptureActivity.class.getSimpleName();
  
  public static final int HISTORY_REQUEST_CODE = 0x0000bacc;
  
  private static final int WHITE = 0xFFFFFFFF;
  private static final int BLACK = 0xFF000000;
  
  private CameraManager cameraManager;
  private CaptureActivityHandler handler;
  private ViewfinderView viewfinderView;
  private boolean hasSurface;
  private MediaPlayer mediaPlayer;
  
  private static final float BEEP_VOLUME = 0.10f;

  private Collection<BarcodeFormat> decodeFormats;
  private Map<DecodeHintType,?> decodeHints;
  private String characterSet;
  private InactivityTimer inactivityTimer;

  private boolean playBeep;
  private boolean vibrate;
  
  private ImageView qrImage;

  ViewfinderView getViewfinderView() {
    return viewfinderView;
  }

  public Handler getHandler() {
    return handler;
  }

  CameraManager getCameraManager() {
    return cameraManager;
  }

  @Override
  public void onCreate(Bundle icicle) {
    super.onCreate(icicle);
    Log.e(TAG, "onCreate");
    try {
    Window window = getWindow();
    window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
    setContentView(R.layout.capture);

    hasSurface = false;
    playBeep = true;

    inactivityTimer = new InactivityTimer(this);
    initBeepSound();
    vibrate = true;
    } catch (Exception e) {
    	e.printStackTrace();
    }
  }

  @Override
  protected void onResume() {
    super.onResume();
    Log.e(TAG, "onResume");
    // CameraManager must be initialized here, not in onCreate(). This is necessary because we don't
    // want to open the camera driver and measure the screen size if we're going to show the help on
    // first launch. That led to bugs where the scanning rectangle was the wrong size and partially
    // off screen.
    cameraManager = new CameraManager(getApplication());

    viewfinderView = (ViewfinderView) findViewById(R.id.viewfinder_view);
    viewfinderView.setCameraManager(cameraManager);
    
    qrImage = (ImageView)findViewById(R.id.qr_image);

    handler = null;

    SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);
    SurfaceHolder surfaceHolder = surfaceView.getHolder();
    if (hasSurface) {
      // The activity was paused but not stopped, so the surface still exists. Therefore
      // surfaceCreated() won't be called, so init the camera here.
      initCamera(surfaceHolder);
    } else {
      // Install the callback and wait for surfaceCreated() to init the camera.
      surfaceHolder.addCallback(this);
    }

    inactivityTimer.onResume();

    decodeFormats = null;
    characterSet = null;
  }

  @Override
  protected void onPause() {
	  Log.e(TAG, "onPause");
    if (handler != null) {
      handler.quitSynchronously();
      handler = null;
    }
    inactivityTimer.onPause();
    cameraManager.closeDriver();
    if (!hasSurface) {
      SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);
      SurfaceHolder surfaceHolder = surfaceView.getHolder();
      surfaceHolder.removeCallback(this);
    }
    super.onPause();
  }

  @Override
  protected void onDestroy() {
	  Log.e(TAG, "onDestroy");
    inactivityTimer.shutdown();
    super.onDestroy();
  }

  @Override
  public boolean onKeyDown(int keyCode, KeyEvent event) {
    switch (keyCode) {
      case KeyEvent.KEYCODE_BACK:
    	  	setResult(RESULT_CANCELED, new Intent());
    	  	onBackPressed();
    	  	return true;
      case KeyEvent.KEYCODE_FOCUS:
      case KeyEvent.KEYCODE_CAMERA:
        // Handle these events so they don't launch the Camera app
        return true;
      // Use volume up/down to turn on light
      case KeyEvent.KEYCODE_VOLUME_DOWN:
        cameraManager.setTorch(false);
        return true;
      case KeyEvent.KEYCODE_VOLUME_UP:
        cameraManager.setTorch(true);
        return true;
    }
    return super.onKeyDown(keyCode, event);
  }


  @Override
  public void surfaceCreated(SurfaceHolder holder) {
    if (holder == null) {
      Log.e(TAG, "*** WARNING *** surfaceCreated() gave us a null surface!");
    }
    if (!hasSurface) {
      hasSurface = true;
      initCamera(holder);
    }
  }

  @Override
  public void surfaceDestroyed(SurfaceHolder holder) {
    hasSurface = false;
  }

  @Override
  public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

  }
  
  private void initBeepSound()
	{
		if (playBeep && mediaPlayer == null)
		{
			// The volume on STREAM_SYSTEM is not adjustable, and users found it
			// too loud,
			// so we now play on the music stream.
			setVolumeControlStream(AudioManager.STREAM_MUSIC);
			mediaPlayer = new MediaPlayer();
			mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
			mediaPlayer.setOnCompletionListener(beepListener);

			AssetFileDescriptor file = getResources().openRawResourceFd(R.raw.beep);
			try
			{
				mediaPlayer.setDataSource(file.getFileDescriptor(), file.getStartOffset(), file.getLength());
				file.close();
				mediaPlayer.setVolume(BEEP_VOLUME, BEEP_VOLUME);
				mediaPlayer.prepare();
			}
			catch (IOException e)
			{
				mediaPlayer = null;
			}
		}
	}

	private static final long VIBRATE_DURATION = 200L;

	private void playBeepSoundAndVibrate()
	{
		if (playBeep && mediaPlayer != null)
		{
			mediaPlayer.start();
		}
		if (vibrate)
		{
			Vibrator vibrator = (Vibrator) getSystemService(VIBRATOR_SERVICE);
			vibrator.vibrate(VIBRATE_DURATION);
		}
	}
	
	private final OnCompletionListener beepListener = new OnCompletionListener()
	{
		public void onCompletion(MediaPlayer mediaPlayer)
		{
			mediaPlayer.seekTo(0);
		}
	};

  /**
   * A valid barcode has been found, so give an indication of success and show the results.
   *
   * @param rawResult The contents of the barcode.
   * @param scaleFactor amount by which thumbnail was scaled
   * @param barcode   A greyscale bitmap of the camera data which was decoded.
   */
  public void handleDecode(Result rawResult, Bitmap barcode, float scaleFactor) {
	  
    inactivityTimer.onActivity();
    playBeepSoundAndVibrate();
    drawResultPoints(barcode, scaleFactor, rawResult);
    
    Intent intent = new Intent();
    intent.putExtra("name", rawResult.getText());
    setResult(RESULT_OK, intent);
    finish();
//    Bitmap bitmap = null;
//	try {
//		bitmap = encodeAsBitmap(rawResult.getText());
//	} catch (WriterException e) {
//		// TODO Auto-generated catch block
//		e.printStackTrace();
//	}
//    qrImage.setImageBitmap(bitmap);
  }
  
  Bitmap encodeAsBitmap(String contents) throws WriterException {
	    String contentsToEncode = contents;
	    if (contentsToEncode == null) {
	      return null;
	    }
	    Map<EncodeHintType,Object> hints = null;
	    String encoding = guessAppropriateEncoding(contentsToEncode);
	    if (encoding != null) {
	      hints = new EnumMap<EncodeHintType, Object>(EncodeHintType.class);
	      hints.put(EncodeHintType.CHARACTER_SET, encoding);
	    }
	    BitMatrix result;
	    try {
	      result = new MultiFormatWriter().encode(contentsToEncode, BarcodeFormat.QR_CODE, 200, 200, hints);
	    } catch (IllegalArgumentException iae) {
	      // Unsupported format
	      return null;
	    }
	    int width = result.getWidth();
	    int height = result.getHeight();
	    int[] pixels = new int[width * height];
	    for (int y = 0; y < height; y++) {
	      int offset = y * width;
	      for (int x = 0; x < width; x++) {
	        pixels[offset + x] = result.get(x, y) ? BLACK : WHITE;
	      }
	    }

	    Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
	    bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
	    return bitmap;
	  }
  
  private static String guessAppropriateEncoding(CharSequence contents) {
	    // Very crude at the moment
	    for (int i = 0; i < contents.length(); i++) {
	      if (contents.charAt(i) > 0xFF) {
	        return "UTF-8";
	      }
	    }
	    return null;
	  }

  /**
   * Superimpose a line for 1D or dots for 2D to highlight the key features of the barcode.
   *
   * @param barcode   A bitmap of the captured image.
   * @param scaleFactor amount by which thumbnail was scaled
   * @param rawResult The decoded results which contains the points to draw.
   */
  private void drawResultPoints(Bitmap barcode, float scaleFactor, Result rawResult) {
    ResultPoint[] points = rawResult.getResultPoints();
    if (points != null && points.length > 0) {
      Canvas canvas = new Canvas(barcode);
      Paint paint = new Paint();
      paint.setColor(getResources().getColor(R.color.result_points));
      if (points.length == 2) {
        paint.setStrokeWidth(4.0f);
        drawLine(canvas, paint, points[0], points[1], scaleFactor);
      } else if (points.length == 4 &&
                 (rawResult.getBarcodeFormat() == BarcodeFormat.UPC_A ||
                  rawResult.getBarcodeFormat() == BarcodeFormat.EAN_13)) {
        // Hacky special case -- draw two lines, for the barcode and metadata
        drawLine(canvas, paint, points[0], points[1], scaleFactor);
        drawLine(canvas, paint, points[2], points[3], scaleFactor);
      } else {
        paint.setStrokeWidth(10.0f);
        for (ResultPoint point : points) {
          if (point != null) {
            canvas.drawPoint(scaleFactor * point.getX(), scaleFactor * point.getY(), paint);
          }
        }
      }
    }
  }

  private static void drawLine(Canvas canvas, Paint paint, ResultPoint a, ResultPoint b, float scaleFactor) {
    if (a != null && b != null) {
      canvas.drawLine(scaleFactor * a.getX(), 
                      scaleFactor * a.getY(), 
                      scaleFactor * b.getX(), 
                      scaleFactor * b.getY(), 
                      paint);
    }
  }

  
  private void sendReplyMessage(int id, Object arg, long delayMS) {
    if (handler != null) {
      Message message = Message.obtain(handler, id, arg);
      if (delayMS > 0L) {
        handler.sendMessageDelayed(message, delayMS);
      } else {
        handler.sendMessage(message);
      }
    }
  }

  private void initCamera(SurfaceHolder surfaceHolder) {
    if (surfaceHolder == null) {
      throw new IllegalStateException("No SurfaceHolder provided");
    }
    if (cameraManager.isOpen()) {
      Log.w(TAG, "initCamera() while already open -- late SurfaceView callback?");
      return;
    }
    try {
      cameraManager.openDriver(surfaceHolder);
      // Creating the handler starts the preview, which can also throw a RuntimeException.
      if (handler == null) {
        handler = new CaptureActivityHandler(this, decodeFormats, decodeHints, characterSet, cameraManager);
      }
    } catch (IOException ioe) {
      Log.w(TAG, ioe);
      displayFrameworkBugMessageAndExit();
    } catch (RuntimeException e) {
      // Barcode Scanner has seen crashes in the wild of this variety:
      // java.?lang.?RuntimeException: Fail to connect to camera service
      Log.w(TAG, "Unexpected error initializing camera", e);
      displayFrameworkBugMessageAndExit();
    }
  }

  private void displayFrameworkBugMessageAndExit() {
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle(getString(R.string.app_name));
    builder.setMessage(getString(R.string.msg_camera_framework_bug));
    builder.setPositiveButton(R.string.ok, new FinishListener(this));
    builder.setOnCancelListener(new FinishListener(this));
    builder.show();
  }

  public void restartPreviewAfterDelay(long delayMS) {
	 Log.e(TAG, "restartPreviewAfterDelay");
    if (handler != null) {
      handler.sendEmptyMessageDelayed(R.id.restart_preview, delayMS);
    }
  }

  public void drawViewfinder() {
    viewfinderView.drawViewfinder();
  }
}
